Perhaps the simplest type of audio product is a basic, line-level preamplifier. Such devices accept line-level signals: ie, a signal with little current flow, typically in the…
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Though we sometimes take for granted that the basic "language" of our measurements is clear to all of our readers, letters to the editor tell us that this is not the case. Periodically, then, we will attempt to explain exactly what our measurements are and what they purport to show. Though those with technical training may find our explanations a bit simplistic, they're aimed at the reader who lacks such experience.
The frequency-response measurement on the Audio Precision is quite straightforward. Like most measurements on this device, the Audio Precision sweeps across the frequency band automatically, one channel at a time, to provide the graphs seen in the charts. The crosstalk measurement is a little more interesting. Each channel is measured separately. The left-to-right crosstalk is a measure of the output from the right channel when a known signal is fed into the left channel and the latter's input is shorted to minimize noise in the reading. L-R crosstalk is measured in dB below the level of the…
John Atkinson explains what is meant by output impedance
When a writer gets deeply embroiled in a subject, what he takes to be simple concepts can still lead to confusion among his readers. Take the subject of component output impedances, which we routinely measure as part of Stereophile's equipment reports. Back in early October, veteran audio writer E. Brad Meyer posted a message on the Compuserve "Audio Hardware" Forum in which even he seemed muddled about this concept. Talking about Stereophile's published measurements of output impedance, he went on to say that "I'm led to wonder…
When a writer gets deeply embroiled in a subject, what he takes to be simple concepts can still lead to confusion among his readers. Take the subject of component output impedances, which we routinely measure as part of Stereophile's equipment reports. Back in early October, veteran audio writer E. Brad Meyer posted a message on the Compuserve "Audio Hardware" Forum in which even he seemed muddled about this concept. Talking about Stereophile's published measurements of output impedance, he went on to say that "I'm led to wonder…
DR. JOHN: Duke Elegant
Blue Note 5 23220 2 (CD). 2000. Mac Rebennack, prod.; Suz Dyer, eng.; Steve Revitte, Tovi Rodriguez, asst. engs. AAD? TT: 66:40
Performance ****?
Sonics ****?
Blue Note 5 23220 2 (CD). 2000. Mac Rebennack, prod.; Suz Dyer, eng.; Steve Revitte, Tovi Rodriguez, asst. engs. AAD? TT: 66:40
Performance ****?
Sonics ****?
For those who complain that there aren't many interesting records out there, here's a disc to savor. The world's finest living New Orleans piano professor, clean and sober and ready to focus, meets one of America's finest composers, a man and pianist whose memory was fêted throughout 1999—the centennial of his birth—with an avalanche of reissues and previously unreleased tidbits.
…
The lease said about my and my fathers trip from the Bureau of Manhattan to our new home the soonest mended. In some way ether I or he got balled up on the grand concorpse and next thing you know we was thretning to swoop down on Pittsfield.
Are you lost daddy I arsked tenderly.
Shut up he explained.
—Ring Lardner, "The Young Immigrunts" (1920)
And you are shocked—shocked—to learn that "Shut up he explained" is something of a catchphrase in our household (footnote 1). Hold that thought.
My wife has wonderfully sensitive hearing, and she calls them as she hears them…
Glenn Again
Speaking of which: You may recall that, last year about this time—"The Fifth Element," March 2002—I was knee-deep in an ultimately fruitless quest to determine whether DSD-on-SACD remasterings of recordings originally made on early PCM equipment could yield sonic benefits. The test piece was Glenn Gould's 1981 recording of J.S. Bach's Goldberg Variations. No conclusions could be drawn, in view of the Accuphase DP-101 SACD decoder's nondefeatable DSD upconversion of "Red Book" CD data, but an interesting development was the discovery of a "ghost" or "mouse" orchestra playing…
Speaking of which: You may recall that, last year about this time—"The Fifth Element," March 2002—I was knee-deep in an ultimately fruitless quest to determine whether DSD-on-SACD remasterings of recordings originally made on early PCM equipment could yield sonic benefits. The test piece was Glenn Gould's 1981 recording of J.S. Bach's Goldberg Variations. No conclusions could be drawn, in view of the Accuphase DP-101 SACD decoder's nondefeatable DSD upconversion of "Red Book" CD data, but an interesting development was the discovery of a "ghost" or "mouse" orchestra playing…
Michael Grace made a headphone amp for his own use. Pretty soon, enough of his friends had asked him to make one for them that he made it a formal product with a model designation and an initial production run of 25 pieces. Those vanished in a trice, and he found himself in the headphone-amp business with a product that was selling briskly by word of mouth, and a few reviews in the professional magazines. I was knocked out by its looks, and asked for a review sample. I was predisposed to like it anyway, in view of sound engineer Jerry Bruck's having used Grace microphone preamplifiers on…
Sidebar: Marantz SA-14 SACD player, from September 2002 (Vol.25 No.9):
Marantz's $2900 SA-14 SACD player has been in the queue waiting to be reviewed, so I'll just sneak in a quick comparison of it here to the Accuphase DP-85, for those enticed by SACD but not prepared to spend $16.5k. Though the SA-14, too, has balanced connections, I ran it only single-ended.
Also very well built—especially given its reasonable price—and handsome to look at, the SA-14 didn't scale the SACD sonic heights reached by the DP-85, particularly when it came to transparency, liquidity, image…
John Atkinson wrote about the Grace 901 in August 2003 (Vol.26 No.8):
After John Marks enthused over the $1495 Grace 901 headphone amplifier in March (pp.45-47), he shipped the review sample (serial number 9085) to me. He wanted me to listen to the unit for myself, not only for pleasure, but also so I could decide whether his recommendation of a Class A rating in our April "Recommended Components" listing was appropriate.
Using two pairs of Sennheiser HD600 headphones, one fitted with the stock three-conductor cable, the other with balanced, dual-mono Clou cable, I compared it…
The Revel Ultima Studios came to me by chance. I'd wanted to review Revel's high-value Performa F-30—see my May 2000 report—but the Studio was offered instead. By the time a pair of Studios had arrived, however, the F-30s were also on their way, and the Studios were put on the back burner. Because of the mix-up, I thought the Studios would be freebies—just listen for a while and send 'em back. I am now obliged to do the honest thing and fess up in public: Many months have passed and the Studios are still here.
Theory
The Ultima Studio is Revel's second-largest speaker. Like the…